EP1410959B1 - Assembly with a base body for a steering wheel and an airbag module - Google Patents

Description

The invention relates to an assembly having a steering wheel base body and an airbag module according to the preamble of claim 1 and claim 12.

For reasons of saving time and cost-effectiveness, gas bag modules in steering wheels are increasingly fastened by snap-in connections. These locking connections should, in addition to ensuring a secure connection of the gas bag module with the steering wheel main body, also be easily solvable to wait or replace the gas bag module. While attaching a component by a latching connection can usually be done in a short operation, required in most known locking connections releasing the locking connection considerably more time.

In the generic EP-A-1 167 132 An attachment of a gas bag module to a steering wheel is described, in which catch hooks of the gas bag module engage in a bent spring wire. The connection thus created is at the same time releasable for all latching hooks by applying a force to the spring wire at one point and displacing it relative to the latching hook. The movement leads to a deformation of the spring wire and a release of the latching hook.

The GB-A-2 336 135 shows a steering wheel having fixed hooks, which can be mounted on a gas bag module, also fixed hook engage. The hooks are connected by a movement senkecht to the axis of the steering wheel with each other.

The invention enables a simultaneous Losën all locking connections in a simple and secure manner.

This is achieved by the features of claim 1 or claim 12 in an assembly mentioned above. It is therefore not necessary to solve each latching connection individually to remove the gas bag module from the steering wheel main body, but all snap-in connections can be solved simultaneously in one step by detecting and moving only one of the locking elements at a central location.

The first locking elements are formed by a plurality of locking hooks and the second locking element is formed by an elongated molding, in which the latching hooks can engage. The molded part can be fastened to the gas bag module or to the steering wheel main body, wherein the snap hooks are then fastened to the respective other component.

The molded part is a rigid punching plate, which is immovable in itself. The molded part is preferably brought by spring force into its locking position and held in this.

Of course, the invention can also be used to attach a gas bag module to other vehicle-mounted components as the steering wheel.

The unlocking takes place without a deformation of one of the locking elements only due to a movement of the locking elements against each other. Preferably, the release of all locking connections done by a purely translational movement.

It can be provided that the group of the first latching elements as a whole is moved in the unlocking direction, i. that no relative movement of the first locking elements takes place to each other.

The steering wheel main body may be formed, for example, by a steering wheel skeleton, wherein a receptacle is provided in the hub area into which the gas bag module is inserted.

The gas bag module may be in the assembled state of the assembly, i. in the case of the gas bag module inserted and latched, be movable against the steering wheel main body in a direction perpendicular to the unlocking direction, without the detent connections being released. This allows the operation of a horn, analogous to a conventional floating horn module.

At the steering wheel main body can be provided accessible from the outside access, which allows a local power transmission to the provided for releasing all locking connections locking element in unlocking. In this way, in the finished steering wheel in which the assembly is assembled, e.g. locally a movement of the locking element in the unlocking direction are caused by the introduction of a special tool from the outside into the steering wheel main body to release all latching connections. For this, e.g. acted on one of the locking elements or on the gas bag module.

Preferably, the group of the first latching elements and / or the at least one second latching element is slidably mounted on the gas bag module or on the steering wheel main body. This has the advantage that not the gas bag module as a whole, but only a locking element or the group of locking elements must be moved to unlock. For this purpose, the group of latching elements can be acted upon by one or more spring elements, so that the latching element or the group of latching elements are returned to a locking position as soon as the force is released. This training can also be used for locking. In this case, when the gas bag module is inserted into the steering wheel main body, the displaceably mounted detent element is first moved in the unlocking direction by a certain amount, whereby it is possible to move the gas bag module into its final position, and then the detent element is in the unlocked direction into its locked position , which corresponds to a home position, moved back, whereby the gas bag module is firmly fixed in the steering wheel body.

• Figur 1 einen schematischen Schnitt durch ein Lenkrad mit einem Gassackmodul;
• Figur 2 eine schematische Ansicht der Rastelemente einer ersten Baugruppe;
• Figur 3 einen schematischen Schnitt entlang der Linie III-III aus Figur 2 durch eine zweite Baugruppe;
• Figur 4 eine schematische Ansicht einer erfindungsgemäßen Baugruppe gemäß einer ersten Ausführungsform der Erfindung während des Einsetzens des Gassackmoduls;
• Figur 5 eine schematische Ansicht der Baugruppe aus Figur 4 in einem verriegelten Zustand;
• Figur 6 eine schematische Ansicht der Baugruppe aus Figur 4 in einem entriegelten Zustand;
• Figur 7 eine perspektivische Darstellung der Anordnung des zweiten Rastelements der Baugruppe aus Figur 4 am Lenkradgrundkörper;
• Figur 8 das zweite Rastelement aus Figur 7 in Verriegelungsstellung;
• Figur 9 das zweite Rastelement aus Figur 7 in Entriegelungsstellung; und
• Figur 10 eine schematische Ansicht des Gassackmoduls gemäß einer zweiten Ausführung der Erfindung.

zur Veranschaulichung der ErfindungFurther features and advantages of the invention will become apparent from the subclaims and from the following description of several embodiments in conjunction with the accompanying drawings. In these show:

• Figure 1 shows a schematic section through a steering wheel with a gas bag module;
• Figure 2 is a schematic view of the locking elements of a first assembly;
• Figure 3 is a schematic section along the line III-III of Figure 2 by a second assembly;
• Figure 4 is a schematic view of an assembly according to the invention according to a first embodiment of the invention during insertion of the airbag module;
• Figure 5 is a schematic view of the assembly of Figure 4 in a locked state;
• Figure 6 is a schematic view of the assembly of Figure 4 in an unlocked condition;
• Figure 7 is a perspective view of the arrangement of the second locking element of the assembly of Figure 4 on the steering wheel body;
• Figure 8 shows the second locking element of Figure 7 in the locked position;
• Figure 9 shows the second locking element of Figure 7 in the unlocked position; and
• Figure 10 is a schematic view of the gas bag module according to a second embodiment of the invention.

to illustrate the invention

In Figure 1, a steering wheel 10 is shown to illustrate the invention, which has a steering wheel main body 12 in a known design, in the hub region, a recess is formed, in which a gas bag module 14 is inserted. The steering wheel main body 12 may be formed, for example, by a skeleton with or without a sheath.

The gas bag module 14 is detachably and reversibly locked on the steering wheel main body 12. For this purpose, a group of first locking elements 18 is attached to the gas bag module, which are designed here as a bolt with latching hooks 20. By way of example, two bolts are shown, but it can, according to the requirements, more or less locking elements 18 may be provided.

The latching hooks 20 of the first latching elements 18 engage in the formation of a latching connection in at least one second latching element 22, which is fastened to the steering wheel main body 12. In the examples shown here, the second latching element 22 is formed by a rigid wire 24, for example a round spring steel with a diameter of approximately 2.5 mm. In the illustrated assembled state of the assembly, the steering wheel main body 12 is firmly connected to the gas bag module 14, since the latching hooks 20 of the first latching elements 18 are engaged with the second latching element 22. In the positive Z-direction, the airbag module 14 can therefore not be moved. In the negative Z direction, however, a shift of the gas bag module 14 against the steering wheel base body 12 for actuating a horn (not shown) is possible, but in which the latching connection is not released.

The second latching element 22 is designed so that it is possible with a corresponding arrangement of the latching hook 20, by a single, central, translational movement of latching elements 18, 22 in a particular geometry determined by the unlocking direction R all locking elements 18, 22 disengaged bring. Here, this is achieved in that the wire 24 is bent into a corresponding shape and can be detected centrally.

A special possibility for the design and arrangement of the latching elements 18, 22 is shown in more detail in FIG. The first latching elements 18 are here designed as latching hooks 20 formed on one side (see FIG. 3) and firmly connected to either the gas bag module 14 or the steering wheel main body 12. In the latching hooks 20 engages in closed latching connection, the second locking element 22 a. The second locking element 22 is here slidably supported in guides 26 (indicated by arrows in Figures 1 and 3), which in turn are fixedly connected either to the steering wheel base 12 or the gas bag module 14.

In the example shown here, the wire 24 is bent in a U-shape. There are three first locking elements 18 are provided. The closed sides 28 of the latching hooks 20 are respectively directed to the interior of the "U". Depending on a first locking element 18 is arranged on each leg and on the closed side of the "U". On the legs of the "U", above the first locking elements 18, the wire 24 in each case an outwardly directed bend 30.

The second locking element 22 engages in the latching hooks 20, so that the latching connections are closed. By the plurality of locking elements 18, 22 a stable, low-backlash attachment of the gas bag module 14 is ensured on the steering wheel body 12. A movement of the gas bag module 14 is possible in this state only in the negative Z direction, but not in the positive Z direction.

By a translational movement of the locking element 22 in unlocking R, which is perpendicular to the Z direction, the locking elements 18, 22 can be disengaged. The locking element 22 moves in the designated xy plane. The second latching element 22 forming wire 24 is during the unlocking movement is not deformed in itself, but only translationally moves as a whole. Also, the first locking elements 18 are rigidly formed here, so that they do not deform during the unlocking movement.

It is also possible to fix the wire 24 rigidly and to hold the group of the first latching elements 18 slidably (possibly via an intermediate carrier element). In this case, of course, the unlocking direction is the negative direction R, indicated by R '.

In any case, can be disengaged by the application of a force at a single point all locking elements.

The respective displaceably mounted group of locking elements can be acted upon by a spring element in the basic position in which the locking connections are closed in order to prevent unintentional unlocking (see Figures 4 to 9).

FIG. 3 shows a variant in which the group of first latching elements 18 on the steering wheel base body 12 and the second latching element 22 on the gas bag module 14 are fastened.

However, it is irrelevant whether the group of the first locking elements 18 is attached to the gas bag module 14 or the steering wheel main body 12, since only the interaction of the locking elements 18, 22 is essential. The example shown in Figure 2 represents only one of many possible embodiments of the locking elements 18, 22.

Preferably, the steering wheel main body 12 and a possibly arranged above panel on a central, accessible from the outside access 32, by a tool (advantageously only with a special tool), the movement of at least one locking element 18, 22 in unlocking R, R 'to the central unlocking can be effected.

The locking elements 18, 22 can also be used as electrical contacts of the horn. In this case, they must be electrically insulated from the gas bag module 14 and the steering wheel main body 12, e.g. by being made of or coated with an insulating material.

In a first embodiment of the invention shown in Figs. 4-10, the second detent member 322 is a rigid, non-moveable, frame-shaped plate 324, e.g. as a punching plate, formed. The plate 324 has a shape that allows it by a purely translational movement simultaneously with all existing first locking elements 318 disengage. The plate 322 is designed so rigid that it is neither plastically nor elastically deformed during the unlocking process.

The plate 324 is held displaceable in the unlocking direction R against the restoring force of a spring element 340 in guides 326 arranged on the steering wheel main body 12. In the embodiment shown, the spring element 340 is formed by a coil spring fixed in a recess of the steering wheel main body 12. In unlocking R extending arms 328 of the rigid guides 326 prevent movement of the plate 324 opposite to an insertion direction of the module (here the direction -Z). In the -Z direction, the plate 324 is supported by the steering wheel main body 12. The guides 326 are open on one side, so that the plate 324 can be easily inserted into the guides 326 during assembly of the steering wheel.

The closed sides of the guides 326 form a stop 350 for the plate 324 which limits movement of the plate against the unlocking direction R due to the force exerted by the spring element 340. In the locking position (FIGS. 5 and 8), the left-hand edge 360 of the plate 324 abuts against the stops 350 in the figures.

The first latching elements 318 are formed by latching hooks 320 fastened to the gas bag module 14, which each have a latching surface 330 and a sliding surface 335 at their free end.

The catch hooks 320 are part of a carrier sheet 370, which also has a substantially flat, frame-shaped base portion 380 connected integrally to the catch hooks 320, over which the carrier sheet 370 e.g. is fixedly attached to the gas bag module 14 via a screw 390 (see Figure 10). The carrier sheet 370 is formed as a stamped sheet metal part. The first locking elements 318 are bent after punching out the carrier sheet, so that they protrude at right angles from the base portion 380. The first latching elements 318 are designed so that all latching hooks 320 point in the same direction (see FIG. 10). The base portion 380 may have a reinforcement function for the bottom of the module 14, e.g. in the case when the module housing or a gas generator carrier forming the bottom of the module consists of plastic. The support plate 370 may be provided to increase the rigidity with beads, folds, flanges or the like.

The plate 324 is designed as a separate component from the gas bag module 14 and from the steering wheel body 12. In the example shown here, the plate 324 is connected to the steering wheel main body only by the inclusion in the guides 326 and the spring element 340 and the gas bag module 14 only in the locked state via the system to the latch hook 320.

In order to fix the gas bag module 14 on the steering wheel main body 12, it is inserted into the steering wheel main body 12 in the negative Z direction (-Z). In this case, the sliding surfaces 335 of the latching hooks 320 come into contact with the plate 324 held in the locking position by the spring element 340 and move them in the unlocking direction R as they progressively insert (see FIG. 4). The plate 324 is moved so far that the latching hooks 320 can move in the -Z direction past the plate 324. However, the plate 324 remains engaged with the guides 326.

After the locking hooks 320 have passed the plate 324 in the -Z direction, the plate 324 moves back into its locking position due to the spring action (see Figure 5). The latching surfaces 330 of the locking hooks 320 now come in train in the positive Z direction in contact with the plate 324, so that the gas bag module 14 is retained. All first locking elements 318 are in the locked state directly with the second locking element 322 into engagement. Further movement of the gas bag module 14 in the -Z direction by a certain amount, for example for actuating a horn, is possible.

To unlock the latching connections, an extension 400 is provided on one side of the plate 324 shown here, which projection is formed by a recess 332 in the steering wheel base 12 from the outside of the steering wheel, e.g. accessible to a special tool. In the example shown here, the spring element 340 engages the plate 324 on the side opposite the extension 400. But extension and spring element can also be arranged elsewhere or designed differently.

In order to release the gas bag module 14 from the steering wheel, the plate 324 is moved by means of the tool against the force of the spring element 340 in its unlocked position (see Figure 9), in which the locking surfaces 330 of the latch hooks 320 with a movement in the positive Z-direction not with come into contact with the plate 324. In this position of the plate 324, the gas bag module 14 can be easily removed by a movement in the Z direction from the steering wheel main body 12.

The latching hooks 320 of all first latching elements 318 are released simultaneously by the displacement of the plate 324 in the unlocking direction R. Since all latching hooks 320 point in the same direction, namely with the open side of the hook in the unlocking direction R (see, for example, Figure 6), all latching connections can be released simultaneously by a single, purely translational movement of the second latching element 322. A displacement that corresponds to the extent of the locking surfaces 330 in unlocking R is sufficient, so that only a short displacement for the second locking element 322 must be provided.

The plate 324 is deformed elastically or plastically neither during manufacture of the lock nor during unlocking.

For the second latching element can also be one of the U-shape of the wire 24 corresponding or any other suitable shape selected. All other features can be realized as described above.

The plate 324 may be attached to the gas bag module 14 instead of the steering wheel main body 12. The latching hooks 320 would then be correspondingly arranged on the steering wheel main body 12.

The spring element 340 may also be provided by one or more leaf springs or an elastic buffer, e.g. be formed of rubber, or by a portion of a foam around the steering wheel. It is also possible not to load the spring element 340 for unlocking, as shown by pressure, but by train. In this case, the spring element 340 can also be realized by an elastic band.

Claims (12)

1. An assembly comprising a steering wheel base body (12) and a gas bag module (14), the gas bag module (14) being adapted to be releasably latched to the steering wheel base body (12) by a group of first detent elements (18; 318) and at least one second detent element (22; 322) being provided and the at least one second detent element (22; 322) being adapted to be brought into reversible locking engagement with the first detent elements (18; 318), the first detent elements (18) being formed by several detent hooks (20) and the second detent element (22) being formed by at least one elongated shaped part into which the detent hooks (20) engage,
   the first detent elements and the at least one second detent element (18, 22; 318, 322), in the assembled condition of the assembly (12, 14), being arranged so as to be movable with respect to each other in an unlocking direction (R; R'), and the detent elements (18, 22; 318, 322) being designed such that by a movement of the second detent element (22; 322) relative to the first detent elements (18; 318) in the unlocking direction (R; R') all the detent connections (18, 22; 318, 322) are released simultaneously in a non-destructive manner,
   characterized in that the shaped part is a rigid plate.
2. The assembly according to claim 1, characterized in that the plate (322) is a stamped sheet metal part.
3. The assembly according to either of the preceding claims, characterized in that the plate (322) is frame-shaped.
4. The assembly according to any of the preceding claims, characterized in that in the assembled condition of the assembly (12, 14), the gas bag module (14) is movable against the steering wheel base body (12) in a direction (-z) perpendicular to the unlocking direction (R; R'), without the detent connections being released.
5. The assembly according to any of the preceding claims, characterized in that provided on the steering wheel base body (12) is an access (32; 332) which is accessible from outside and permits a transmission of force onto the detent element (22; 322), provided for releasing all the detent connections, in the unlocking direction (R; R').
6. The assembly according to any of the preceding claims, characterized in that the group of the first detent elements (18; 318) and/or the at least one second detent element (22; 322) are/is displaceably fastened to the gas bag module (14) or to the steering wheel base body (12), respectively.
7. The assembly according to claim 6, characterized in that the displaceably fastened detent element (322) is acted upon by a spring element (340) which endeavours to hold the detent element (322) in a locking position.
8. The assembly according to claim 6 or 7, characterized in that provided for the displaceably fastened detent element (322) is at least one stop (350) against which the detent element (322) lies in its locking position.
9. The assembly according to any of the preceding claims, characterized in that the first detent elements (18; 318) each have a detent hook (20; 320) and all the detent hooks (20; 320) are oriented in the same direction.
10. The assembly according to any of the preceding claims, characterized in that the movement for releasing the detent connections is a purely translational movement.
11. The assembly according to any of the preceding claims, characterized in that the second detent element (22; 322) is designed to be so rigid that it is not deformed during the unlocking process.
12. An assembly comprising a steering wheel base body (12) and a gas bag module (14), the gas bag module (14) being adapted to be releasably latched to the steering wheel base body (12) by a group of first detent elements (18; 318) and at least one second detent element (22; 322) being provided and the at least one second detent element (22; 322) being adapted to be brought into reversible locking engagement with the first detent elements (18; 318),
    the first detent elements and the at least one second detent element (18, 22; 318, 322), in the assembled condition of the assembly (12, 14), being arranged so as to be movable with respect to each other in an unlocking direction (R; R'), and the detent elements (18, 22; 318, 322) being designed such that by a movement of the second detent element (22; 322) relative to the first detent elements (18; 318) in the unlocking direction (R; R') all the detent connections (18, 22; 318, 322) are released simultaneously in a non-destructive manner,
    characterized in that the second detent element (22; 322) is designed to be so rigid that it is not deformed during the unlocking process, the group of the first detent elements (18; 318) and/or the at least one second detent element (22; 322) are/is displaceably fastened to the gas bag module (14) or to the steering wheel base body (12), respectively, and the displaceably fastened detent element (322) or group of detent elements is acted upon by a separate spring element (340) which endeavours to hold the detent element (322) or the group of detent elements in a locking position.

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